What is the difference between a defendant's conviction for sexual assault under section 288 of the Criminal Code for placing his arm around the victim's shoulder?

"In the zealous quest to bring respondent to 'justice,' the majority opinion makes no effort to distinguish People v. Webb (1958) 158 Cal.App.2d 537 [323 P.2d 141]. Webb held that a defendant's conviction of section 288 could be based on an act of oral copulation but not on the defendant's act of [11 Cal.App.4th 577] placing his arm around the victim's shoulder as he led him into the bungalow where the oral copulation occurred. (Id. at p. 542 [323 P.2d 141] )